External storage device unit

ABSTRACT

An external storage device includes an external storage device main includes a thin type external storage device module formed into a package sealed on one side from a storage element containing at least one non-volatile semiconductor memory device, and a flat type external connection terminal connected to an input/output terminal of the storage element and led and exposed to a backside of the module, and an external storage device unit that includes an external storage device main detachable section for engaging, insertedly attaching and detaching the external storage device main, a resilient contact electrically connecting to the external connection terminal of the external storage device main, and at least a part of a circuit for driving and controlling the storage element.

This application is a continuation of application Ser. No. 08/657,198,filed Jun. 3, 1996, now abandoned, which is a division of applicationSer. No. 08/205,451, filed Mar. 4, 1994, now U.S. Pat. No. 5,550,709.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to this external storage devices that arereleasably or exchangeably used for storage equipment and externalstorage medium devices.

2. Description of the Related Art

Two types of storage devices, or memory elements, that which are capableof recording and saving various data, have been utilized. One isincorporated and fixed within storage equipment or devices, and theother is releasably or exchangeably incorporated in storage equipment ordevices. In the latter type, the external storage device, for example, afloppy disk, can freely be attached or detached by a one touchoperation. The floppy disks, being storage mediums, can separately beused depending on purpose and object. This therefore produces easierdata reduction with optional classification, recording, and saving.However, a problem arises in the floppy disks described. First, the dataoccasionally disappears when recording or saving the data to produce thedisadvantage of less reliability. Second, the floppy disk has a slowaccess time. Also, when employing smaller sized floppy disks in responseto a miniaturization goal, the storage area of the storage medium iscorrespondingly smaller thereby reducing storage capacity. This resultsin an adverse effect in realizing both the compact size and highcapacity. On the other hand, in semiconductor memory devices used as anexternal storage device, such as IC memory cards, the problems of floppydisks, such as low reliability on recording and saving data and slowaccess time, can largely be overcome. In general, IC memory cardscomprise a functional circuit in which circuit components containingsemiconductor memory devices or elements are mounted on a substrate. Aresin case incorporates therein with the functional circuit as an insideattachment. A cover covers and seals an opening surface of the resincase, and external connection terminals, such as two piece connectors,are attached on one edge of the resin case and electrically connect thefunctional circuit and the storage equipment.

However, IC memory cards are assembled with a large number of componentsand parts. Thus, a relatively complicated structure is requiredimpacting the thickness of the IC memory card, resulting in difficultyin realizing the compact size. Further, disadvantages arise in practicaluse because of lower cost performance and production yields in massproducing, in addition to the decreased releasability or fluctuatedreleasability to the storage equipment and device.

SUMMARY OF THE INVENTION

An object of the present invention is to provide an external storagedevice having a simplified structure with satisfactory productionyields.

Another object of the present invention is to provide an externalstorage device with a high reliability with respect to recording andsaving the data.

Another object of the present invention is to provide an externalstorage device having a rapid access time.

Still another object of the present invention is to provide an externalstorage device having high releasability for the storage equipment anddevice.

The external storage device according to the present invention comprisesof an external storage device main and an external storage device unit.The external storage device main includes a thin external storage devicemodule formed into a package sealed on one side from a storage elementcontaining at least one non-volatile semiconductor memory device, and aflat type external connection terminal connected to an input/outputterminal of the storage element and led and exposed to a backside of theexternal storage device module. The external storage device unitincludes a mechanism for engaging, insertedly attaching and detachingthe external storage device main, a resilient contact electricallyconnecting to the flat type external connection terminal of the externalstorage device main.

In the external storage device according to the present invention, theexternal storage device main may preferably be formed into a packagestructure sealed on one side. However for easier handling, the externalstorage device main may also preferably be in the form of a card typestructure attached on a supporting plate. The external storage deviceunit may preferably be assembled and incorporated with a part of or allof the control circuit components or parts, such as semiconductorelements, performing the control function.

The external storage device of a preferred embodiment has a higherintegration with a memory capacity to an extent of 16 M-bits per chip.In addition, the device is preferably provided as a main memory with anon-volatile semiconductor memory device which does not require a powersupply for maintaining storage. The main memory is incorporated into thepackage sealed on one side to produce a thin type external storagedevice module or external storage device main. Thus, the externalstorage device module is easily achieved in a thin structure and at alower cost by, for example, a transfer mold system. To mount a card typeexternal storage device main to the external storage device unit, aninsertion system at the side surface of the external storage device unitmay be provided. An external connection terminal is led and positionedin a plane with a rear-side of the external storage device main. Hence,a highly reliable electrical connection can easily be achieved whenattaching and detaching by a one touch system the external storagedevice unit. In a card type device, the external storage device itselfmaintains and exhibits satisfactory releasability for the storageequipment and devices. The card type external storage device main canreadily be attached and detached to the external storage device unit,and realizes a function equivalent to a floppy disk device as it is, andsimultaneously a reliability of electrical connecting and disconnectingdue to the attaching and detaching.,

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top perspective view of a first example of an externalstorage device main according to the present invention.

FIG. 2 is a bottom perspective view of the first example of an externalstorage device main shown in FIG. 1.

FIG. 3 is an enlarged sectional view taken along line III--III of FIG.1.

FIG. 4 is a top perspective view of a second example of an externalstorage device main according to the present invention.

FIG. 5 is an enlarged sectional view taken along line V--V of FIG. 4.

FIG. 6 is a plan view of an example of an external storage device inwhich the external storage device main shown in FIG. 4 is assembled ontoan external storage device unit.

FIG. 7 is a sectional view taken along line C--C of FIG. 6.

FIG. 8 is a plan view showing essentials of an example of anotherexternal storage device in which the external storage device main shownin FIG. 7 is assembled into an external storage device unit.

FIG. 9 is a sectional view taken along line IX--IX of FIG. 8.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Embodiments invention are described referring to FIGS. 1 to 9 asfollows.

The present invention has been achieved by means of a cleverly conceivedstructure and profile where the devices such as semiconductor memorydevices or elements are mounted on the conventional substrates and inaccordance with the fact that a non-volatile semiconductor memory deviceor element with a capacity of 16 M-bits per chip corresponds to a 2M-byte floppy disk.

FIGS. 1 to 3 show a first example of an external storage device moduleconstituting features of the thin type external storage device mainaccording to the invention, where FIG. 1 is a perspective view onsurface which is one-sided sealed on one side by a transfer mold, FIG. 2a perspective view of a rear-side surface which is one-side sealed bythe transfer mold, and FIG. 3 is a sectional view taken along lineIII--III of FIG. 1.

In this first example, a card type external storage device module 1 isconstructed such that a storage element 2, such as a 16 M-bit NAND flashtype non-volatile semiconductor memory device, is connected on a surfaceof the through hole type resin based wiring substrate 3 by wire-bonding4. The storage element 2 may, if required, include an anti-electrostaticelement for preventing electrostatic destruction, the anti-electrostaticelement being used for input and output to the memory element 2. Insteadof the wire bonding 4, flip chip bonding may also be performed todirectly adhere the rear side of the memory element 2 on the resin basedwiring substrate 3. The substrate 3 is preferably a thin wiringsubstrate, for example, an insulative substrate member made ofglass-epoxy resin or the like. The resin based wiring substrate 3, asurface on which is mounted the storage element and 2 including a NANDflash type non-volatile semiconductor memory device, is sealed on oneside by a transfer mold layer 5. More specifically, the external storagedevice module 1 (which is designated the external storage device mainwhen considered by itself) is sealed on one side and formed into a flatplate shaped thin type package with an entire thickness of less thanabout 1 mm. The transfer mold layer 5 may generally be formed of epoxybased resin or the like. However, it also may preferably be formed of acomposition containing inorganics.

On the other hand, the one-side sealed through hole type resin basedwiring substrate 3, in other words, the backside surface 1a of theexternal storage device module 1 is arranged with a plane shaped or flattype terminal 1b taken out through the through hole to form the externalstorage device module 1. The plane shaped terminal 1b is preferably gold(Au)-plated on its surface, and functions as an external connectionterminal for electrically connecting to a contact member of an externalstorage device unit which is described later. In this example, the planeshaped terminal 1b is gold-plated to increase the reliability of theelectrical connection. However, such plating is not always required.

FIGS. 4 and 5 show a second structural example of the structure of acard type external storage device main 1' in which the external storagedevice module 1 is attached on a card shaped supporter 6, where FIG. 4is a perspective view, and FIG. 5 is a sectional view taken along lineV--V of FIG. 4. The card shaped supporter 6 may preferably be, forexample, an insulative resin plate.

In the second example above, for a simplified operation the externalstorage device module 1 is incorporated into the card shaped supporter 6having length 42.8 mm, a width of less than 27 mm, and a thickness 0.76mm, wherein the size of the supporter 6 is half the card size regulatedin accordance with JEIDA. In more detail, the external storage devicemodule 1 is assembled into the card shaped supporter 6. The supporter 6has a recessed portion in which the external storage device module 1 canpreviously be inserted and attached. As shown in FIGS. 4 and 5, asurface of the external connection terminal 1b of the external storagedevice module 1 is inserted, attached, and exposed in the same plane asa main surface of the card shaped supporter 6, thereby forming the cardtype storage device main 1'.

FIGS. 6 and 7 show a structural example wherein the card type externalstorage device main 1' is attached to an external storage device unit 7,where FIG. 6 is a plan view, and FIG. 7 is a sectional view taken alongline VII--VII of FIG. 6.

In this example, the card type external storage device main 1' hasstorage elements on side thereof. The external storage device module 1,in which the storage element 2, including at least a non-volatilesemiconductor memory chip, is sealed on one side by the transfer moldlayer 5, is inserted and attached into the card shaped supporter 6 toproduce the card type external storage device main 1'. The card typeexternal storage device main 1' is releasably attached on and installedinto the external storage device unit 7 to form an external storagedevice 8. The external storage device unit 7 can be electricallyconnected to the plane shaped external connection terminal 1b providedon the external storage device module 1 on the card type externalstorage device main 1'. Simultaneously, the external storage device unit7 has a structure that the card type external storage device main 1' isreleasably attached therefrom.

To releasably attach and detach the card type external storage devicemain 1', is that the external storage device unit 7 has on its surface arecessed portion corresponding to the shape and dimensions of the cardtype external storage device main 1'. A surface on the recessed portionis arranged with a contact 7a that preferably corresponds to theexternal connection terminal 1b of the card type external storage devicemain 1'. To attach and detach the card type external storage device main1' smoothly, a guide structure 7b and a one touch structure 7c arepreferably provided. When the card type external storage device main 1'is inserted, attached or removed from the external storage device unit7, smooth insertion and extraction is provided by the guide structure7b, placed on which is a side-surface of the unit 7 in the insertion andextraction direction. Simultaneously, the one touch structure 7c ispreferably placed at a tip end of card 1 and provides secure attaching,electrical connection, and release thereof. If required, a micro-switchsystem for supplying electricity to the card type external storagedevice main 1' may preferably be to be provided with the one touchstructure 7c. In FIGS. 6 and 7, element 7d represents an IC elementgroup constituting a part of a drive and control circuit for the storageelement 2 including the non-volatile semiconductor memory chip, whichthe card type external storage device section 1' possesses. The contact7a for electrically connecting to the external connection terminal 1b ismade, for example, using a pin type contact having a spring mechanism.

The external storage device 8, including the card type external storagedevice main 1', according to the present invention is not limited to theexample as described above. For example, the present invention alsoincludes the structure shown in a plan view of FIG. 8 and in a sectionalview of FIG. 9 taken along line IX--IX of FIG. 8. The card type externalstorage device main 1' may preferably be inserted or extracted from aside-surface of a case 9. The case 9 preferably has on one side a pinconnection 9a. The case 9 may, for example, be sized to have a length of85.6 mm, a width of 54.0 mm, and a thickness of 3.3 mm. In more detail,the case 9 is also preferably provided with an insertion and extractionsection 9b, such as a space or gap, for attaching, through inserting andextracting, the card type external storage device main 1' from theside-surface of the case 9. A push button 9c may preferably be providedon the case 9 to achieve attaching or detaching to th e external storagedevice unit 7. In particular, when the card type external storage devicemain 1' is attached by inserting and extracting from the side surface ofthe external storage device unit 7, compared to a structure having asurface recessed portion for attaching the card type external storagedevice main 1', it is correspondingly not required to enlarge an outersurface required for attaching the external storage device. Thus, thiseasily realizes a compact size, fine view, and high reliability due toincorporation (inside mount) of the card type external storage devicemain 1'.

It is understood that the present invention is not limited to theexamples as hereinbefore described. For example, the card type externalstorage device main 1 according to the present invention may be used, asit is, without attaching it on or to the card shaped supporter 6.

As is apparent from the description above, the external storage deviceaccording to the present invention has a higher integration andprovides, even in one chip, a larger memory capacity of a non-volatilesemiconductor memory device as a main memory. In addition, basicconstruction is employed in that the external storage device main has acompact structure, and the main memory is sealed on one side, by atransfer mold. The use of the one-side sealing system and thenon-volatile semiconductor memory device provides a thin structure andcompact size of the external storage device. The releaseable onattaching and ease of carrying provide simple operation and handling,and result in a lower cost. When forming the external storage device bycombining with the external storage device unit, reliability in the cardtype external storage device can be improved, thereby preventing damageor connection failures of the external connection terminal with a gradedreleasability due to satisfactory slidability. A great number ofadvantages in practical use are obtained, such as optionally detachingor easily carrying the external storage device main without thepossibility of external damage, and a larger capacity of recording orsaving data even given the compact size.

What is claimed is:
 1. A card shaped external storage device unitcapable of interfacing with a card shaped external storage device mainthat stores data, the card shaped external storage device maincomprising a storage element containing at least one flash typenon-volatile semiconductor memory device capable of being electricallywritten with the data to be stored, and a flat type connection terminalformed on a surface of the card shaped external storage device main, thecard shaped external storage device unit comprising:means capable ofengaging, insertedly and rigidly attaching and detaching the externalstorage device main; a resilient contact capable of electricallyconnecting to the connection terminal of the external storage devicemain; and means capable of driving and controlling the storage element,the driving and controlling means being capable of causing the flashtype non-volatile semiconductor memory device to receive, store, andoutput data, and the driving and controlling means comprising at leastan integrated circuit.
 2. The card shaped external storage device unitas set forth in claim 1, wherein the card shaped external storage deviceunit has a space for receiving the card shaped external storage devicemain therein.
 3. The card shaped external storage device unit as setforth in claim 1, wherein the card shaped external storage device unitfurther comprises an opening capable of receiving the card shapedexternal storage device main formed on one side of the card shapedexternal storage device unit.
 4. The card shaped external storage deviceunit as set forth in claim 1, wherein a thickness of the card shapedexternal storage device unit is approximatly 3.3 mm.
 5. The card shapedexternal storage device unit as set forth in claim 1, wherein theresilient contact is coupled to the means for driving and controllingthe storage element in the external storage device unit.
 6. The cardshaped external storage device unit as set forth in claim 1, wherein themeans for driving and controlling is capable of causing a NAND flashtype non-volatile semiconductor memory device of the external storagedevice main to receive, store, and output data.
 7. The card shapedexternal storage device unit as set forth in claim 1, further comprisinga micro-switch system capable of switching electricity supplied to thecard shaped external storage device main.
 8. The card shaped externalstorage device unit as set forth in claim 2, wherein the space has awidth large enough to receive the external storage device main, whichhas an area less than a card size area specified in JEIDA standards, anda height great enough to receive the external storage device main, whichhas a thickness of approximately 0.76 mm.
 9. The card shaped externalstorage device unit as set forth in claim 6, wherein the means fordriving and controlling and the NAND flash type non-volatilesemiconductor memory device of the external storage device main arecapable of being connected so that data to be stored is directlycommunicated through the resilient contact and the connection terminal.